Firstly, a ``Cognitive Design Guideline¡Ç¡Ç is proposed for designing WWW-based CAI system by applying effective concepts and models in education, which have been proposed in cognitive psychology. A new CAI system was developed as an augmented material of lecturing ``Human Interface Science¡Ç¡Ç by Internet. This was designed based on the proposed cognitive guideline and the field experiment was conducted to compare this new CAI system with the conventional CAI system. It was confirmed that the new CAI system be better to promote learning process than the conventional one.